README.txt
==========

Supporting Materials for Report

Title: An Exploratory Data Mining Study of Re-entry Events: Foundations for Multi-Modality Sensing and Data Fusion
Affiliation: Sandia National Laboratories, 1515 Eubank Boulevard NE, Albuquerque, NM 87123
Authors: Vedant Sawal, Elizabeth Silber
Date: 04/14/2025

Overview:
---------
This dataset compiles publicly reported reentry events recorded between 1995-2024. The study intends to provide the foundation for Multi-Modality Sensing and Data Fusion.

How to Use The Dataset: The dataset contains two files:
1. "Artificial_Event_Database.xlsx"
2. "Space Shuttles 1995-2011.xlsx"


"Artificial_Event_Database.xlsx" contains a sheet:
 - Observed reentries 1995-2024 :The Table contains data from reentry events of the artificial objects from 1995-2024

"Space Shuttles 1995-2011.xlsx" contains a sheet:
 - Observed reentries 1995-2011: The Table contains data from reentry events of the space shuttles from 1995-2011 

The dataset is presented as a structured table with multiple fields covering:
- Date and time of reentry and sightings
- Geographic details like latitude, longitude, and region for entry, terminal, and debris points
- Vehicle characteristics like model, production year, height, diameter, width and mass, and country of origin 
- flight parameters like angles to landing, midpoint latitude and midpoint longitude 	
- Sources of information: There are three columns for sources of information. Along with the other sources the following common sources were also used to compile the dataset:

	1.Aerospace Reentry DB:	A Center for Orbital and Reentry Debris Studies (CORDS) database that documents objects and payloads reentries, including predicted reentry times, geographic information, and uncertainties. The CSV file export from this page was used to extract aerospace reentry prediction data for certain events in this report. The csv file is submitted as a separate file "Reentry_History_Spreadsheet_04-08-25.csv"

	2.SatObs: A PDF document that lists the comprehensive table of visual sightings of natural reentries of earth satellites. The document was sourced from a website dedicated to comprehensive information on all aspects of visual Satellite observation

	3.Wikipedia- Shuttle Missions: A Wikipedia page that lists all the shuttle missions.

Common Sources Websites:
------------------------
1. Aerospace Reentry DB
   URL: https://aerospace.org/reentries/grid?field_reentry_type_target_id%5B0%5D=31&field_reentry_sighting_value=All&format_select=table&reentry_timezone_selector=America/Chicago&page=7 
   
2. SatObs
   URL: https://www.satobs.org/reentry/Visually_Observed_Natural_Re-entries_latest_draft.pdf

3. Wikipedia- Shuttle Missions
   URL: https://en.wikipedia.org/wiki/List_of_Space_Shuttle_missions


Each row in the dataset corresponds to one reported test event.

Dataset Column Descriptions:
----------------------------
1. SSN – Space Surveillance Network ID
2. Date – Includes Year, Month, Day of reentry/sighting
3. Reentry Time – Time in Hours, Minutes, Seconds
4. Time Zone – Time zone of event
5. Country/Region – Location of the reported event
6. Possible Entry Point/Sighting 1 – Includes Latitude, Longitude, Altitude, and Region
7. Possible Terminal Point/Sighting 2 – Includes Latitude, Longitude, Altitude, and Region
8. Debris/Sighting Location – Includes Region, Latitude, Longitude
9. Speed – Estimated reentry or flight speed [km/s]
10. Entry Angle – Angle of descent at atmospheric entry [deg]
11. Type of Vehicle – Rocket Body (R/B), Payload, or Debris etc.
12. Model – Vehicle model
13. Production Year – Approximate vehicle production year
14. Vehicle Dimensions – Height [m], Diameter [m], Width [m], Mass [kg]
16. Country of Origin – Country where the object was manufactured
17. Reentry Type – Controlled, or uncontrolled
18. State at Reentry – Intact or Beak up.
19. Mode of Observation – Sonic boom, visual
20. Azimuth Angles To Landing – Estimated approach direction [deg]
21. Source 1 / Source 2 /Source 3 – Sources used for the reentry events
23. Aerospace Reentry Prediction – Includes:
    - International Designator
    - Predicted Date (Year, Month, Day)
    - Predicted Time (UTC)
    - Reported Uncertainty (+/- hrs using 20% rule)

Contact:
--------
For questions or comments about this dataset or report, contact:
vsawal@sandia.gov
esilbe@sandia.gov


DISCLAIMER: We note that no single source included in this dataset should be regarded as authoritative or entirely accurate. The entries do not represent official confirmations and are to be treated strictly as open-source indications subject to further verification and clarification. Given the inherent limitations and potential inaccuracies of publicly available information, users are advised to interpret the data with caution and to consider additional corroborative evidence when conducting subsequent analyses or drawing definitive conclusions.